1. Field of the Invention
This invention relates to retaining wall blocks, and more particularly, to a self interlocking, mortarless block system having vertically adjacent blocks interconnected with hollow pegs.
2. Related Art
Masonry construction has been used to construct above and below walls, retaining walls, and foundations for centuries. Conventional masonry systems is the assembly of building blocks by laying blocks adjacent to each other with some type of mortar placed in-between two such adjacent blocks. Upon setting or hardening, the mortar acts as an adhesive and holds the blocks together.
One of the principal disadvantages with wanting to build a conventional above or below grade wall, retaining wall or foundation wall is the need for a skilled mason. The typical homeowner, property owner, or contractor cannot easily build such a wall because of the many issues involved, e.g., the needed consistency of the mortar, the aligning of adjacent blocks, the amount and level of mortar between the blocks, the cost of a skilled mason, and most of all, the availability of a skilled mason. Therefore, there is a need for a self interlocking block system that is mortarless, wherein an unskilled laborer can easily and quickly, in all types of weather, build an above or below grade wall, retaining wall, or foundation wall.
Another disadvantage with building a conventional wall is that this activity is weather dependent. When using mortar, a laborer can only build a wall under the appropriate weather conditions. That is, it is impossible to build a wall using mortar if the weather is below freezing, or, it is too wet. Therefore, there is a need for a self interlocking block system that is mortarless such that building a wall is not dependent on the weather conditions.
Another disadvantage with building a conventional wall is that the activity is very labor intensive. It takes a lot of labor to lay each block in the wall, by making sure that each block has the appropriate amount of mortar around the edges, is level, and is square and “plumb” with the rest of the masonry units in the wall.
Another disadvantage with building a conventional wall is that the activity is very time consuming. It takes a lot of time to mix the ingredients comprising the mortar, transporting the mortar to the skilled mason, and precisely placing the mortar between each adjacent masonry block, leveling and “plumbing” the whole wall, “tooling” the masonry joints, and finally cleaning the spilled masonry cement from the wall surfaces and around the construction site.
Another disadvantage with building a conventional wall is that the activity is very expensive. The cost of the mortar, mixing the mortar, transporting the mortar to the wall, placing the mortar in the adjacent masonry blocks, leveling and plumbing all blocks, tooling the masonry joints, cleaning the mortar off the wall when finished, and cleaning up the “mortar mess” when the job is complete.
Another disadvantage with building a conventional wall is the minimal amount of lateral structural load capacity of the finished wall. When a force, such as the soil around the outside of a masonry foundation wall, exerts lateral loads against the exterior of the wall, the conventional masonry wall (i.e., its hollow cores are not filled with grout and supplemented with vertical steel reinforcing re-bar or steel horizontal reinforcing mesh is not periodically and structurally imbedded into the horizontal mortar joints between the masonry blocks) is subject to failure by being “pushed in” by the lateral load of the unstable foundation fill material. Therefore, there is a need for a self interlocking, mortarless block system that produces a finished wall capable of withstanding increased lateral load forces.
There are several types of mortarless block systems that are available; however, each one fails to satisfy the current need for a self locking, mortarless masonry block system. Specifically, almost all the prior art provide virtually no lateral load capability without the need for grout and vertical reinforcement, e.g., steel re-bar, embedded within the grout.
In U.S. Pat. Nos. 6,298,632 and 5,715,635 to Sherwood for a modular building block unit, a building block is disclosed having multiple, circular apertures extending through the height of the blocks. The apertures, however, provide no specific purpose or function in the use of these blocks in building a wall. The patent merely states that a block of that invention may be formed with holes extending through the thickness of the block as a means for reducing the weight of the block, such as in conventional blocks. The focus of these patents is to vertically interlock two adjacent blocks via mounting strips attached to the blocks. Furthermore, there is no teaching or suggestion that the holes of two vertically adjacent blocks must be aligned. A top block may slide horizontally on top of a bottom block along the mounting blocks such that the holes of the blocks either align or do not align. Lastly, a problem with this type of mortarless block is that the block cannot be manufactured in a single step process. That is, the block cannot be manufactured with a conventional block machine wherein the mounting strips are an integral part of the block itself. The mounting strips must be secured to the block after the block is made. Therefore, there is a need for a self interlocking, mortarless block system wherein the blocks of the system are manufactured in a single step without the need to secure other components to the block.
In U.S. Pat. No. 6,050,044 to McIntosh, a block is disclosed that is very similar to a conventional “LEGO” toy block wherein it has multiple, closed posts extending up from the top face of the block which interlock into the bottom of a vertically adjacent block. In addition, this block has side-by-side connectors that permit the connecting of blocks horizontally for the construction of weight bearing spanning structures. Due to the difficulties in making a masonry block with such posts extending from the surface of the block, this block is intended to be made of plastic by injection molding. Therefore, there is a need for a masonry, self interlocking block that is easily manufactured with a conventional block machine.
In U.S. Pat. No. 5,966,889 to Zinner, a block is disclosed wherein a “tongue” of one block fits within a “groove” of a vertically adjacent block. The purpose of this block is to eliminate the need for reinforced concrete with reinforcement rods positioned in vertical lines of block holes of a conventional block. Furthermore, the '889 block system requires an adhesive material to join two adjacent blocks wherein a dry powder is placed between two blocks as they are laid. The wall is later wet, thereby causing the powder to bond the blocks together. As above, this patent also recognizes the problems with conventional block building using mortar due to the settling of the blocks and the requirement of skilled labor. Therefore, there is a need for a self interlocking block system that does not require the use of an adhesive material nor mortar to hold two adjacent blocks together, and that can be used quickly and efficiently by an unskilled laborer.
In U.S. Pat. No. 5,711,130 to Shatley, a building block system is disclosed that uses pins to join two vertically adjacent blocks. Because the pins are solid and not hollow, there is no means for further supporting assembled blocks with a filler material. Also, the pins are not intended to contact vertically other pins, such that the pins are “fatter” on the top side to prevent the pins from falling through the holes to the block below. Therefore, a wall of these building blocks does not provide a vertical shaft from the top of the wall to the bottom of the wall in which additional support materials can be placed. Also, this block system provides virtually no lateral load capabilities. Therefore, there is a need for a self interlocking block system having a means for vertically supporting a wall.
In U.S. Pat. No. 3,005,282 to Christiansen, a toy building block is disclosed that is similar in design to the block of the '044 patent to McIntosh. As such, this toy block is impossible to manufacture out of a masonry material on a conventional block machine due to the protrusions on the top surface of the block. Therefore, there is a need for a self interlocking, masonry block that can be manufactured using a conventional block machine.
In addition to the above, patented block systems, there are other commercially available block systems that attempt to solve the problems in the art. For example, Azar Mortarless Building Systems, Inc. offers an Azar Block mortarless system that only requires a grout fill. The disadvantage with the Azar Block is that there is no means for vertically aligning two adjacent blocks, and no means for providing a vertical shaft through a wall of Azar Blocks for additional support. In addition, the laborer must still add a grout fill.
Cercorp Initiatives, Inc. provides a FlexLock block that interlock using ground-mating surfaces and post-tension tendons. That is, the FlexLock block system requires both masonry and hardware components. Protrusions on the top face of a first block fit within recesses in the bottom face of a vertically adjacent block. The disadvantages with the FlexLock block system is that it also does not provide a vertical shaft extending from the top of a wall to the bottom of the wall that can be used for additional support, that it is difficult to use a conventional block machine to manufacture blocks with such protrusions on the top surface, and that it is difficult to manufacture recesses and protrusions on masonry blocks that actually interlock. Also, this block system provides virtually no lateral load capabilities.
Versa-Lok Retaining Wall Systems, a division of Kiltie Corporation, provides a Versa-Lok system similar to the '130 patent wherein vertically adjacent blocks are interlocked with pins. Thus, the same disadvantages with the '130 patent are present in the Versa-Lok system. Also, this block system provides virtually no lateral load capabilities.
In addition to the above noted disadvantages, none of these prior art block systems are portable or reusable. That is, these systems cannot be pre-manufactured, or pre-assembled, and then transported to a final destination. Also, once a wall is built using any of these masonry, block systems, the wall cannot be disassembled without destroying the wall such that the component parts of the wall cannot be reused in constructing a new wall. Therefore, there is a need for a self interlocking block system with which a wall can be pre-assembled, easily transported to a final destination, and secured at that destination. There is still a further need for a self interlocking block system that provides for a wall to be easily disassembled and its component parts reused in the construction of another wall.
Therefore, despite the many attempts, there is still a need for a mortarless, interlocking block system that can be easily and quickly used to build an above or below grade wall, a retaining wall, or a foundation wall.